I almost bought a new 2019 Sierra AT4 today, it had 11 miles on it. I had read this forum as part of researching. I noticed that there looked to be water spots on the inside of the rear window. I had the salesman take it through the car wash. There was a stream of water down the back window. They said that they had never heard of this before, but were going to apply caulk and for me to come back tomorrow.
The price sounds like a good deal, but I don't know if I want to mess with the potential problems that ya'll are having. My current truck is a 2014 Sierra with 234,000 miles, I'm debating about seeing how long it will go before it breaks down.
Thanks for all the great info guys.
James